326 THE EAR
ear, local applications are raore_ useful Sensitivity reactions may follow the
topical use of antibiotics particularly penicillin and chloramphenicol, and
the prolonged use of antibiotic ear drops may cause the development of
resistant strains of organisms or the onset of a fungus infection. The use of
antibiotics whether as drops or powder must be governed by bacteriological
studies identifying the sensitivities of the infecting organisms. JBLydrocorti-
sone and neomycin_eaŁ_drops may. be prescribed initially and other anti-
biotics such as jrajnycetia, gentajpu'cin and polymyxin B are valuable against
the mixed growths of Gram^riegative organisms. Alternatively, other topical
substances such as boric acid ear drops or spirit ear drops may be instilled.
Drops should be instilled by rilling the meatus with solution then applying
intermittent pressure over the tragus so that the drops are encouraged to
pass through the perforation into the middle ear. In cases in which there
is a large perforation and scanty discharge treatment by insufflation of
powder may be effective. Boric acid with or without the addition of 1 per
cent iodine is often effective and the antibiotics previously mentioned may
also be employed in powdered form. These medical or conservative measures
are applicable in cases of tubotympanic disease where an active state may
be made quiescent or inactive in many cases, but in others the ear may never
become completely dry despite the removal of any focus of infection in the
upper respiratory tract. When suppuration ceases, leaving a dry perforation,
instructions should be given that water should not be allowed to enter the
ear at any time. Swimming may only be permitted if the meatus is completely
occluded by a suitable ear-plug and a bathing cap is worn. Diving and
under-water swimming should be forbidden.
The hazard of reinfection persists as long as a perforation remains and
closure is a further desirable step in treatment particularly as some improve-
ment in hearing may follow. Myringoplasty is the operation employed for
repairing a perforation from which there should have been no discharge
for 6 months. The conditions necessary for the success of this operation are
good cochlear function, a patent Eustachian tube and a healthy external
meatus. Various operative techniques have been developed, the majority
of operations employing a graft of t^mpnraH^ fascjg which is applied to
the prepared surface of the drumhead and the adjacent bony meatal wall
(fig. 176, A, p. 343). Even if hearing is not materially improved, the
presence of an intact membrane reduces the risk of reinfection and swirnrning,
etc. may be more freely permitted.
When disease is located in the attic and mastoid antrum there is a greater
risk of complications calling for active surgical treatment to place the ear
in a safe condition. Granulation tissue protruding through a perforation
may prevent drainage from the middle ear and should be destroyed by
cauterization with a fused bead of silver nitrate or chromic acid. Large
granulations nSay be removed by ring curette and cup forceps under general
anaesthesia and magnification. An aural polypus may also obstruct drainage
and is best removed with a wire snare under a general anaesthetic. If
adequate drainage is established from the middle ear by these procedures
medical treatment may overcome the infection and a dry ear result. Such
ears, however, require prolonged observation and in the event of recurring
bouts of otorrhoea more radical surgery is indicated. The presence of chole-
steatoma is a clear indication for surgery to remove all diseased tissue from